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performance tuning - Mathematica computes too slowly at the start of a session



Everyone, I'm a Mathematica new user. I find it a problem that, when I start a new Mathematica session, it executes too slowly for the first command (say, "1+1", it may take a few seconds before it gives the "2").


Can you help me resolve the problem? (My Mathematica is running on OS X 10.10)




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